[40.09] A search for molecular gas at the far end of the Hubble sequence

T. Boeker (STScI), U. Lisenfeld (IAA), E. Schinnerer (Caltech)

We will present the results of a search for molecular gas in
a sample of about 50 extremely late-type spirals selected
for distance and inclination. We used the IRAM 30m telescope
to determine the molecular gas content, as traced by the
CO(1-0) and (2-1) lines, in the central region of these
disk-dominated, unevolved galaxies. Measuring the molecular
gas content is an important step in understanding the
formation of the compact nuclear star clusters that are
found in the photocenters of the majority of late-type
spirals. The mere existence of these clusters is puzzling
because gravity hardly provides a vector pointing at the
center on these shallow disks that do not have a massive
bulge. In addition, recent spectroscopic studies have shown
that many of the nuclear clusters are rather young (less
than a few 100 Myrs) which implies that their formation is a
recurrent event. However, it is unclear what the feeding
mechanism of these nuclear starbursts are. The results of
our survey will yield a representative view of the central
gas reservoirs in the latest-type spirals, allow a
comparison to earlier-type spirals with more prominent
bulges, and will produce a source catalog for
high-resolution interferometric follow-up studies to
investigate the mechanism(s) that funnel gas towards the
very nucleus.

The author(s) of this abstract have provided an email address
for comments about the abstract:
boeker@stsci.edu